August 11, 2026 Derecho – National Weather Service (.gov)

August 11, 2026 Derecho  National Weather Service (.gov)

August 11th was a very active day with multiple rounds of severe weather. A cluster of strong to severe storms impacted northwest and north central Indiana in the morning around the US 30 corridor, dropping hail the size of baseballs in Starke County, IN! By late morning, a strong MCS was observed quickly moving east through northern Illinois. This line of storms produced destructive damaging wind gusts up to 100 mph in far NW Indiana! In our forecast area, La Porte, Starke, Marshall, and St Joseph (IN) counties saw the most damage with wind gusts of up to 75 mph. This system rapidly weakened as it moved into north central Indiana, with wind damage reports becoming much more sporadic.

In addition to the severe weather, repeated heavy rainfall over the same areas caused flash flooding.  Per SPC at 5:07 PM EDT 8/11/26: "The MCS that moved from eastern Iowa to northern Indiana today has been preliminarily confirmed as a derecho. Based on the preliminary information thus far it began around 12Z this morning and continued to at least 1725 UTC (although will be evaluated later if the continuation to near Cincinnati may be included). The maximum measured gust received thus far was 86 kts (99 mph) in Gary, Indiana. Just a reminder that official 2026 derechos will be confirmed in 2027